diff --git a/.vscode/launch.json b/.vscode/launch.json
index 886089d1..09ccbd59 100644
--- a/.vscode/launch.json
+++ b/.vscode/launch.json
@@ -11,7 +11,7 @@
             "skipFiles": ["<node_internals>/**"],
             "type": "node",
             "args": ["generate"],
-            "cwd": "${workspaceFolder}/samples/blog/zenstack"
+            "cwd": "${workspaceFolder}/samples/blog"
         },
         {
             "name": "Debug with TSX",
diff --git a/packages/cli/src/actions/action-utils.ts b/packages/cli/src/actions/action-utils.ts
index 287c5593..49655622 100644
--- a/packages/cli/src/actions/action-utils.ts
+++ b/packages/cli/src/actions/action-utils.ts
@@ -1,10 +1,13 @@
-import { loadDocument } from '@zenstackhq/language';
-import { isDataSource } from '@zenstackhq/language/ast';
+import { createZModelServices, loadDocument, type ZModelServices } from '@zenstackhq/language';
+import { isDataSource, isPlugin, Model } from '@zenstackhq/language/ast';
+import { getLiteral } from '@zenstackhq/language/utils';
 import { PrismaSchemaGenerator } from '@zenstackhq/sdk';
 import colors from 'colors';
 import fs from 'node:fs';
 import path from 'node:path';
+import { fileURLToPath } from 'node:url';
 import { CliError } from '../cli-error';
+import { PLUGIN_MODULE_NAME } from '../constants';
 
 export function getSchemaFile(file?: string) {
     if (file) {
@@ -34,7 +37,9 @@ export function getSchemaFile(file?: string) {
 }
 
 export async function loadSchemaDocument(schemaFile: string) {
-    const loadResult = await loadDocument(schemaFile);
+    const { ZModelLanguage: services } = createZModelServices();
+    const pluginDocs = await getPluginDocuments(services, schemaFile);
+    const loadResult = await loadDocument(schemaFile, pluginDocs);
     if (!loadResult.success) {
         loadResult.errors.forEach((err) => {
             console.error(colors.red(err));
@@ -47,6 +52,63 @@ export async function loadSchemaDocument(schemaFile: string) {
     return loadResult.model;
 }
 
+export async function getPluginDocuments(services: ZModelServices, fileName: string): Promise<string[]> {
+    // parse the user document (without validation)
+    const parseResult = services.parser.LangiumParser.parse(fs.readFileSync(fileName, { encoding: 'utf-8' }));
+    const parsed = parseResult.value as Model;
+
+    // balk if there are syntax errors
+    if (parseResult.lexerErrors.length > 0 || parseResult.parserErrors.length > 0) {
+        return [];
+    }
+
+    // traverse plugins and collect "plugin.zmodel" documents
+    const result: string[] = [];
+    for (const decl of parsed.declarations.filter(isPlugin)) {
+        const providerField = decl.fields.find((f) => f.name === 'provider');
+        if (!providerField) {
+            continue;
+        }
+
+        const provider = getLiteral<string>(providerField.value);
+        if (!provider) {
+            continue;
+        }
+
+        let pluginModelFile: string | undefined;
+
+        // first try to treat provider as a path
+        let providerPath = path.resolve(path.dirname(fileName), provider);
+        if (fs.existsSync(providerPath)) {
+            if (fs.statSync(providerPath).isDirectory()) {
+                providerPath = path.join(providerPath, 'index.js');
+            }
+
+            // try plugin.zmodel next to the provider file
+            pluginModelFile = path.resolve(path.dirname(providerPath), PLUGIN_MODULE_NAME);
+            if (!fs.existsSync(pluginModelFile)) {
+                // try to find upwards
+                pluginModelFile = findUp([PLUGIN_MODULE_NAME], path.dirname(providerPath));
+            }
+        }
+
+        if (!pluginModelFile) {
+            // try loading it as a ESM module
+            try {
+                const resolvedUrl = import.meta.resolve(`${provider}/${PLUGIN_MODULE_NAME}`);
+                pluginModelFile = fileURLToPath(resolvedUrl);
+            } catch {
+                // noop
+            }
+        }
+
+        if (pluginModelFile && fs.existsSync(pluginModelFile)) {
+            result.push(pluginModelFile);
+        }
+    }
+    return result;
+}
+
 export function handleSubProcessError(err: unknown) {
     if (err instanceof Error && 'status' in err && typeof err.status === 'number') {
         process.exit(err.status);
diff --git a/packages/cli/src/actions/generate.ts b/packages/cli/src/actions/generate.ts
index e80c219d..2db079e1 100644
--- a/packages/cli/src/actions/generate.ts
+++ b/packages/cli/src/actions/generate.ts
@@ -64,7 +64,7 @@ async function runPlugins(schemaFile: string, model: Model, outputPath: string,
     for (const plugin of plugins) {
         const provider = getPluginProvider(plugin);
 
-        let cliPlugin: CliPlugin;
+        let cliPlugin: CliPlugin | undefined;
         if (provider.startsWith('@core/')) {
             cliPlugin = (corePlugins as any)[provider.slice('@core/'.length)];
             if (!cliPlugin) {
@@ -78,12 +78,14 @@ async function runPlugins(schemaFile: string, model: Model, outputPath: string,
             }
             try {
                 cliPlugin = (await import(moduleSpec)).default as CliPlugin;
-            } catch (error) {
-                throw new CliError(`Failed to load plugin ${provider}: ${error}`);
+            } catch {
+                // plugin may not export a generator so we simply ignore the error here
             }
         }
 
-        processedPlugins.push({ cliPlugin, pluginOptions: getPluginOptions(plugin) });
+        if (cliPlugin) {
+            processedPlugins.push({ cliPlugin, pluginOptions: getPluginOptions(plugin) });
+        }
     }
 
     const defaultPlugins = [corePlugins['typescript']].reverse();
diff --git a/packages/cli/src/constants.ts b/packages/cli/src/constants.ts
index 586537af..72463404 100644
--- a/packages/cli/src/constants.ts
+++ b/packages/cli/src/constants.ts
@@ -1,2 +1,5 @@
 // replaced at build time
 export const TELEMETRY_TRACKING_TOKEN = '<TELEMETRY_TRACKING_TOKEN>';
+
+// plugin-contributed model file name
+export const PLUGIN_MODULE_NAME = 'plugin.zmodel';
diff --git a/packages/language/res/stdlib.zmodel b/packages/language/res/stdlib.zmodel
index 7ac57ba3..f1b46e84 100644
--- a/packages/language/res/stdlib.zmodel
+++ b/packages/language/res/stdlib.zmodel
@@ -174,29 +174,6 @@ function hasSome(field: Any[], search: Any[]): Boolean {
 function isEmpty(field: Any[]): Boolean {
 } @@@expressionContext([AccessPolicy, ValidationRule])
 
-/**
- * The name of the model for which the policy rule is defined. If the rule is
- * inherited to a sub model, this function returns the name of the sub model.
- *
- * @param optional parameter to control the casing of the returned value. Valid
- * values are "original", "upper", "lower", "capitalize", "uncapitalize". Defaults
- * to "original".
- */
-function currentModel(casing: String?): String {
-} @@@expressionContext([AccessPolicy])
-
-/**
- * The operation for which the policy rule is defined for. Note that a rule with
- * "all" operation is expanded to "create", "read", "update", and "delete" rules,
- * and the function returns corresponding value for each expanded version.
- *
- * @param optional parameter to control the casing of the returned value. Valid
- * values are "original", "upper", "lower", "capitalize", "uncapitalize". Defaults
- * to "original".
- */
-function currentOperation(casing: String?): String {
-} @@@expressionContext([AccessPolicy])
-
 /**
  * Marks an attribute to be only applicable to certain field types.
  */
@@ -658,56 +635,3 @@ attribute @meta(_ name: String, _ value: Any)
  * Marks an attribute as deprecated.
  */
 attribute @@@deprecated(_ message: String)
-
-/* --- Policy Plugin --- */
-
-/**
- * Defines an access policy that allows a set of operations when the given condition is true.
- *
- * @param operation: comma-separated list of "create", "read", "update", "delete". Use "all" to denote all operations.
- * @param condition: a boolean expression that controls if the operation should be allowed.
- */
-attribute @@allow(_ operation: String @@@completionHint(["'create'", "'read'", "'update'", "'post-update'","'delete'", "'all'"]), _ condition: Boolean)
-
-/**
- * Defines an access policy that allows the annotated field to be read or updated.
- * You can pass a third argument as `true` to make it override the model-level policies.
- *
- * @param operation: comma-separated list of "create", "read", "update", "delete". Use "all" to denote all operations.
- * @param condition: a boolean expression that controls if the operation should be allowed.
- * @param override: a boolean value that controls if the field-level policy should override the model-level policy.
- */
-// attribute @allow(_ operation: String @@@completionHint(["'create'", "'read'", "'update'", "'delete'", "'all'"]), _ condition: Boolean, _ override: Boolean?)
-
-/**
- * Defines an access policy that denies a set of operations when the given condition is true.
- *
- * @param operation: comma-separated list of "create", "read", "update", "delete". Use "all" to denote all operations.
- * @param condition: a boolean expression that controls if the operation should be denied.
- */
-attribute @@deny(_ operation: String @@@completionHint(["'create'", "'read'", "'update'", "'post-update'","'delete'", "'all'"]), _ condition: Boolean)
-
-/**
- * Defines an access policy that denies the annotated field to be read or updated.
- *
- * @param operation: comma-separated list of "create", "read", "update", "delete". Use "all" to denote all operations.
- * @param condition: a boolean expression that controls if the operation should be denied.
- */
-// attribute @deny(_ operation: String @@@completionHint(["'create'", "'read'", "'update'", "'delete'", "'all'"]), _ condition: Boolean)
-
-/**
- * Checks if the current user can perform the given operation on the given field.
- *
- * @param field: The field to check access for
- * @param operation: The operation to check access for. Can be "read", "create", "update", or "delete". If the operation is not provided,
- * it defaults the operation of the containing policy rule.
- */
-function check(field: Any, operation: String?): Boolean {
-} @@@expressionContext([AccessPolicy])
-
-/**
- * Gets entity's value before an update. Only valid when used in a "post-update" policy rule.
- */
-function before(): Any {
-} @@@expressionContext([AccessPolicy])
-
diff --git a/packages/language/src/index.ts b/packages/language/src/index.ts
index ab577c7f..d6e0d72f 100644
--- a/packages/language/src/index.ts
+++ b/packages/language/src/index.ts
@@ -51,7 +51,7 @@ export async function loadDocument(
     );
 
     // load additional model files
-    const pluginDocs = await Promise.all(
+    const additionalDocs = await Promise.all(
         additionalModelFiles.map((file) =>
             services.shared.workspace.LangiumDocuments.getOrCreateDocument(URI.file(path.resolve(file))),
         ),
@@ -69,7 +69,7 @@ export async function loadDocument(
     }
 
     // build the document together with standard library, plugin modules, and imported documents
-    await services.shared.workspace.DocumentBuilder.build([stdLib, ...pluginDocs, document, ...importedDocuments], {
+    await services.shared.workspace.DocumentBuilder.build([stdLib, ...additionalDocs, document, ...importedDocuments], {
         validation: {
             stopAfterLexingErrors: true,
             stopAfterParsingErrors: true,
diff --git a/packages/language/src/utils.ts b/packages/language/src/utils.ts
index 762187b3..3e24285f 100644
--- a/packages/language/src/utils.ts
+++ b/packages/language/src/utils.ts
@@ -447,8 +447,9 @@ export function getAuthDecl(decls: (DataModel | TypeDef)[]) {
     return authModel;
 }
 
+// TODO: move to policy plugin
 export function isBeforeInvocation(node: AstNode) {
-    return isInvocationExpr(node) && node.function.ref?.name === 'before' && isFromStdlib(node.function.ref);
+    return isInvocationExpr(node) && node.function.ref?.name === 'before';
 }
 
 export function isCollectionPredicate(node: AstNode): node is BinaryExpr {
diff --git a/packages/language/src/validators/function-invocation-validator.ts b/packages/language/src/validators/function-invocation-validator.ts
index a740b86e..9e75a18a 100644
--- a/packages/language/src/validators/function-invocation-validator.ts
+++ b/packages/language/src/validators/function-invocation-validator.ts
@@ -20,7 +20,6 @@ import {
     getLiteral,
     isCheckInvocation,
     isDataFieldReference,
-    isFromStdlib,
     typeAssignable,
 } from '../utils';
 import type { AstValidator } from './common';
@@ -52,43 +51,39 @@ export default class FunctionInvocationValidator implements AstValidator<Express
             return;
         }
 
-        if (isFromStdlib(funcDecl)) {
-            // validate standard library functions
-
-            // find the containing attribute context for the invocation
-            let curr: AstNode | undefined = expr.$container;
-            let containerAttribute: DataModelAttribute | DataFieldAttribute | undefined;
-            while (curr) {
-                if (isDataModelAttribute(curr) || isDataFieldAttribute(curr)) {
-                    containerAttribute = curr;
-                    break;
-                }
-                curr = curr.$container;
+        // find the containing attribute context for the invocation
+        let curr: AstNode | undefined = expr.$container;
+        let containerAttribute: DataModelAttribute | DataFieldAttribute | undefined;
+        while (curr) {
+            if (isDataModelAttribute(curr) || isDataFieldAttribute(curr)) {
+                containerAttribute = curr;
+                break;
             }
+            curr = curr.$container;
+        }
 
-            // validate the context allowed for the function
-            const exprContext = this.getExpressionContext(containerAttribute);
+        // validate the context allowed for the function
+        const exprContext = this.getExpressionContext(containerAttribute);
 
-            // get the context allowed for the function
-            const funcAllowedContext = getFunctionExpressionContext(funcDecl);
+        // get the context allowed for the function
+        const funcAllowedContext = getFunctionExpressionContext(funcDecl);
 
-            if (exprContext && !funcAllowedContext.includes(exprContext)) {
-                accept('error', `function "${funcDecl.name}" is not allowed in the current context: ${exprContext}`, {
-                    node: expr,
-                });
-                return;
-            }
+        if (exprContext && !funcAllowedContext.includes(exprContext)) {
+            accept('error', `function "${funcDecl.name}" is not allowed in the current context: ${exprContext}`, {
+                node: expr,
+            });
+            return;
+        }
 
-            // TODO: express function validation rules declaratively in ZModel
+        // TODO: express function validation rules declaratively in ZModel
 
-            const allCasing = ['original', 'upper', 'lower', 'capitalize', 'uncapitalize'];
-            if (['currentModel', 'currentOperation'].includes(funcDecl.name)) {
-                const arg = getLiteral<string>(expr.args[0]?.value);
-                if (arg && !allCasing.includes(arg)) {
-                    accept('error', `argument must be one of: ${allCasing.map((c) => '"' + c + '"').join(', ')}`, {
-                        node: expr.args[0]!,
-                    });
-                }
+        const allCasing = ['original', 'upper', 'lower', 'capitalize', 'uncapitalize'];
+        if (['currentModel', 'currentOperation'].includes(funcDecl.name)) {
+            const arg = getLiteral<string>(expr.args[0]?.value);
+            if (arg && !allCasing.includes(arg)) {
+                accept('error', `argument must be one of: ${allCasing.map((c) => '"' + c + '"').join(', ')}`, {
+                    node: expr.args[0]!,
+                });
             }
         }
 
diff --git a/packages/language/test/utils.ts b/packages/language/test/utils.ts
index 4b60ce42..690b2490 100644
--- a/packages/language/test/utils.ts
+++ b/packages/language/test/utils.ts
@@ -5,11 +5,13 @@ import path from 'node:path';
 import { expect } from 'vitest';
 import { loadDocument } from '../src';
 
+const pluginDocs = [path.resolve(__dirname, '../../plugins/policy/plugin.zmodel')];
+
 export async function loadSchema(schema: string) {
     // create a temp file
     const tempFile = path.join(os.tmpdir(), `zenstack-schema-${crypto.randomUUID()}.zmodel`);
     fs.writeFileSync(tempFile, schema);
-    const r = await loadDocument(tempFile);
+    const r = await loadDocument(tempFile, pluginDocs);
     expect(r).toSatisfy(
         (r) => r.success,
         `Failed to load schema: ${(r as any).errors?.map((e) => e.toString()).join(', ')}`,
@@ -22,7 +24,8 @@ export async function loadSchemaWithError(schema: string, error: string | RegExp
     // create a temp file
     const tempFile = path.join(os.tmpdir(), `zenstack-schema-${crypto.randomUUID()}.zmodel`);
     fs.writeFileSync(tempFile, schema);
-    const r = await loadDocument(tempFile);
+
+    const r = await loadDocument(tempFile, pluginDocs);
     expect(r.success).toBe(false);
     invariant(!r.success);
     if (typeof error === 'string') {
diff --git a/packages/plugins/policy/package.json b/packages/plugins/policy/package.json
index 4c60ab7d..4187bd9f 100644
--- a/packages/plugins/policy/package.json
+++ b/packages/plugins/policy/package.json
@@ -13,7 +13,8 @@
     "author": "ZenStack Team",
     "license": "MIT",
     "files": [
-        "dist"
+        "dist",
+        "plugin.zmodel"
     ],
     "exports": {
         ".": {
@@ -26,6 +27,10 @@
                 "default": "./dist/index.cjs"
             }
         },
+        "./plugin.zmodel": {
+            "import": "./plugin.zmodel",
+            "require": "./plugin.zmodel"
+        },
         "./package.json": {
             "import": "./package.json",
             "require": "./package.json"
@@ -33,7 +38,6 @@
     },
     "dependencies": {
         "@zenstackhq/common-helpers": "workspace:*",
-        "@zenstackhq/sdk": "workspace:*",
         "@zenstackhq/runtime": "workspace:*",
         "ts-pattern": "catalog:"
     },
diff --git a/packages/plugins/policy/plugin.zmodel b/packages/plugins/policy/plugin.zmodel
new file mode 100644
index 00000000..ae04a41b
--- /dev/null
+++ b/packages/plugins/policy/plugin.zmodel
@@ -0,0 +1,72 @@
+/**
+ * Defines an access policy that allows a set of operations when the given condition is true.
+ *
+ * @param operation: comma-separated list of "create", "read", "update", "post-update", " "delete". Use "all" to denote all operations.
+ * @param condition: a boolean expression that controls if the operation should be allowed.
+ */
+attribute @@allow(_ operation: String @@@completionHint(["'create'", "'read'", "'update'", "'post-update'","'delete'", "'all'"]), _ condition: Boolean)
+
+/**
+ * Defines an access policy that allows the annotated field to be read or updated.
+ * You can pass a third argument as `true` to make it override the model-level policies.
+ *
+ * @param operation: comma-separated list of "create", "read", "update", "post-update", "delete". Use "all" to denote all operations.
+ * @param condition: a boolean expression that controls if the operation should be allowed.
+ * @param override: a boolean value that controls if the field-level policy should override the model-level policy.
+ */
+// attribute @allow(_ operation: String @@@completionHint(["'create'", "'read'", "'update'", "'post-update'", "'delete'", "'all'"]), _ condition: Boolean, _ override: Boolean?)
+
+/**
+ * Defines an access policy that denies a set of operations when the given condition is true.
+ *
+ * @param operation: comma-separated list of "create", "read", "update", "post-update", "delete". Use "all" to denote all operations.
+ * @param condition: a boolean expression that controls if the operation should be denied.
+ */
+attribute @@deny(_ operation: String @@@completionHint(["'create'", "'read'", "'update'", "'post-update'","'delete'", "'all'"]), _ condition: Boolean)
+
+/**
+ * Defines an access policy that denies the annotated field to be read or updated.
+ *
+ * @param operation: comma-separated list of "create", "read", "update", "post-update", "delete". Use "all" to denote all operations.
+ * @param condition: a boolean expression that controls if the operation should be denied.
+ */
+// attribute @deny(_ operation: String @@@completionHint(["'create'", "'read'", "'update'", "'delete'", "'all'"]), _ condition: Boolean)
+
+/**
+ * Checks if the current user can perform the given operation on the given field.
+ *
+ * @param field: The field to check access for
+ * @param operation: The operation to check access for. Can be "read", "create", "update", "post-update", or "delete". If the operation is not provided,
+ * it defaults the operation of the containing policy rule.
+ */
+function check(field: Any, operation: String?): Boolean {
+} @@@expressionContext([AccessPolicy])
+
+/**
+ * Gets entity's value before an update. Only valid when used in a "post-update" policy rule.
+ */
+function before(): Any {
+} @@@expressionContext([AccessPolicy])
+
+/**
+ * The name of the model for which the policy rule is defined. If the rule is
+ * inherited to a sub model, this function returns the name of the sub model.
+ *
+ * @param optional parameter to control the casing of the returned value. Valid
+ * values are "original", "upper", "lower", "capitalize", "uncapitalize". Defaults
+ * to "original".
+ */
+function currentModel(casing: String?): String {
+} @@@expressionContext([AccessPolicy])
+
+/**
+ * The operation for which the policy rule is defined for. Note that a rule with
+ * "all" operation is expanded to "create", "read", "update", and "delete" rules,
+ * and the function returns corresponding value for each expanded version.
+ *
+ * @param optional parameter to control the casing of the returned value. Valid
+ * values are "original", "upper", "lower", "capitalize", "uncapitalize". Defaults
+ * to "original".
+ */
+function currentOperation(casing: String?): String {
+} @@@expressionContext([AccessPolicy])
diff --git a/packages/plugins/policy/src/column-collector.ts b/packages/plugins/policy/src/column-collector.ts
index 37d9df11..ed68c76d 100644
--- a/packages/plugins/policy/src/column-collector.ts
+++ b/packages/plugins/policy/src/column-collector.ts
@@ -1,10 +1,10 @@
+import { KyselyUtils } from '@zenstackhq/runtime';
 import type { ColumnNode, OperationNode } from 'kysely';
-import { DefaultOperationNodeVisitor } from '@zenstackhq/sdk';
 
 /**
  * Collects all column names from a query.
  */
-export class ColumnCollector extends DefaultOperationNodeVisitor {
+export class ColumnCollector extends KyselyUtils.DefaultOperationNodeVisitor {
     private columns: string[] = [];
 
     collect(node: OperationNode) {
diff --git a/packages/plugins/policy/src/policy-handler.ts b/packages/plugins/policy/src/policy-handler.ts
index 92f5e74c..c90bb563 100644
--- a/packages/plugins/policy/src/policy-handler.ts
+++ b/packages/plugins/policy/src/policy-handler.ts
@@ -7,6 +7,7 @@ import {
     QueryUtils,
     RejectedByPolicyError,
     RejectedByPolicyReason,
+    SchemaUtils,
     type CRUD_EXT,
 } from '@zenstackhq/runtime';
 import {
@@ -17,7 +18,6 @@ import {
     type MemberExpression,
     type SchemaDef,
 } from '@zenstackhq/runtime/schema';
-import { ExpressionVisitor } from '@zenstackhq/sdk';
 import {
     AliasNode,
     BinaryOperationNode,
@@ -270,7 +270,7 @@ export class PolicyHandler<Schema extends SchemaDef> extends OperationNodeTransf
         }
 
         const fields = new Set<string>();
-        const fieldCollector = new (class extends ExpressionVisitor {
+        const fieldCollector = new (class extends SchemaUtils.ExpressionVisitor {
             protected override visitMember(e: MemberExpression): void {
                 if (isBeforeInvocation(e.receiver)) {
                     invariant(e.members.length === 1, 'before() can only be followed by a scalar field access');
diff --git a/packages/runtime/src/index.ts b/packages/runtime/src/index.ts
index b5018f05..cff4960f 100644
--- a/packages/runtime/src/index.ts
+++ b/packages/runtime/src/index.ts
@@ -1,2 +1,4 @@
 export * from './client';
+export * as KyselyUtils from './utils/kysely-utils';
+export * as SchemaUtils from './utils/schema-utils';
 export type { JsonArray, JsonObject, JsonValue } from './utils/type-utils';
diff --git a/packages/sdk/src/default-operation-node-visitor.ts b/packages/runtime/src/utils/kysely-utils.ts
similarity index 100%
rename from packages/sdk/src/default-operation-node-visitor.ts
rename to packages/runtime/src/utils/kysely-utils.ts
diff --git a/packages/sdk/src/expression-utils.ts b/packages/runtime/src/utils/schema-utils.ts
similarity index 98%
rename from packages/sdk/src/expression-utils.ts
rename to packages/runtime/src/utils/schema-utils.ts
index ec423767..8c0824d4 100644
--- a/packages/sdk/src/expression-utils.ts
+++ b/packages/runtime/src/utils/schema-utils.ts
@@ -10,7 +10,7 @@ import type {
     NullExpression,
     ThisExpression,
     UnaryExpression,
-} from './schema';
+} from '../schema';
 
 export class ExpressionVisitor {
     visit(expr: Expression): void {
diff --git a/packages/sdk/src/index.ts b/packages/sdk/src/index.ts
index c74b1419..649a7201 100644
--- a/packages/sdk/src/index.ts
+++ b/packages/sdk/src/index.ts
@@ -1,7 +1,5 @@
 import * as ModelUtils from './model-utils';
 export * from './cli-plugin';
-export * from './expression-utils';
-export * from './default-operation-node-visitor';
 export { PrismaSchemaGenerator } from './prisma/prisma-schema-generator';
 export * from './ts-schema-generator';
 export * from './zmodel-code-generator';
diff --git a/packages/sdk/src/model-utils.ts b/packages/sdk/src/model-utils.ts
index 7b54aa96..198e59ac 100644
--- a/packages/sdk/src/model-utils.ts
+++ b/packages/sdk/src/model-utils.ts
@@ -3,7 +3,6 @@ import {
     isLiteralExpr,
     isModel,
     isTypeDef,
-    Model,
     type AstNode,
     type Attribute,
     type AttributeParam,
@@ -14,6 +13,7 @@ import {
     type Enum,
     type EnumField,
     type FunctionDecl,
+    type Model,
     type Reference,
     type TypeDef,
 } from '@zenstackhq/language/ast';
diff --git a/packages/testtools/src/client.ts b/packages/testtools/src/client.ts
index 4a23280e..27133f83 100644
--- a/packages/testtools/src/client.ts
+++ b/packages/testtools/src/client.ts
@@ -1,5 +1,4 @@
 import { invariant } from '@zenstackhq/common-helpers';
-import { loadDocument } from '@zenstackhq/language';
 import type { Model } from '@zenstackhq/language/ast';
 import { PolicyPlugin } from '@zenstackhq/plugin-policy';
 import { ZenStackClient, type ClientContract, type ClientOptions } from '@zenstackhq/runtime';
@@ -15,6 +14,7 @@ import { Client as PGClient, Pool } from 'pg';
 import { expect } from 'vitest';
 import { createTestProject } from './project';
 import { generateTsSchema } from './schema';
+import { loadDocumentWithPlugins } from './utils';
 
 export function getTestDbProvider() {
     const val = process.env['TEST_DB_PROVIDER'] ?? 'sqlite';
@@ -116,7 +116,7 @@ export async function createTestClient<Schema extends SchemaDef>(
     if (options?.usePrismaPush) {
         invariant(typeof schema === 'string' || schemaFile, 'a schema file must be provided when using prisma db push');
         if (!model) {
-            const r = await loadDocument(path.join(workDir, 'schema.zmodel'));
+            const r = await loadDocumentWithPlugins(path.join(workDir, 'schema.zmodel'));
             if (!r.success) {
                 throw new Error(r.errors.join('\n'));
             }
diff --git a/packages/testtools/src/schema.ts b/packages/testtools/src/schema.ts
index 516d445a..b78bcbc8 100644
--- a/packages/testtools/src/schema.ts
+++ b/packages/testtools/src/schema.ts
@@ -1,5 +1,4 @@
 import { invariant } from '@zenstackhq/common-helpers';
-import { loadDocument } from '@zenstackhq/language';
 import { TsSchemaGenerator } from '@zenstackhq/sdk';
 import type { SchemaDef } from '@zenstackhq/sdk/schema';
 import { execSync } from 'node:child_process';
@@ -10,6 +9,7 @@ import path from 'node:path';
 import { match } from 'ts-pattern';
 import { expect } from 'vitest';
 import { createTestProject } from './project';
+import { loadDocumentWithPlugins } from './utils';
 
 function makePrelude(provider: 'sqlite' | 'postgresql', dbUrl?: string) {
     return match(provider)
@@ -44,7 +44,7 @@ export async function generateTsSchema(
     const noPrelude = schemaText.includes('datasource ');
     fs.writeFileSync(zmodelPath, `${noPrelude ? '' : makePrelude(provider, dbUrl)}\n\n${schemaText}`);
 
-    const result = await loadDocument(zmodelPath);
+    const result = await loadDocumentWithPlugins(zmodelPath);
     if (!result.success) {
         throw new Error(`Failed to load schema from ${zmodelPath}: ${result.errors}`);
     }
@@ -82,7 +82,7 @@ export function generateTsSchemaFromFile(filePath: string) {
 
 export async function generateTsSchemaInPlace(schemaPath: string) {
     const workDir = path.dirname(schemaPath);
-    const result = await loadDocument(schemaPath);
+    const result = await loadDocumentWithPlugins(schemaPath);
     if (!result.success) {
         throw new Error(`Failed to load schema from ${schemaPath}: ${result.errors}`);
     }
@@ -114,7 +114,7 @@ export async function loadSchema(schema: string, additionalSchemas?: Record<stri
         }
     }
 
-    const r = await loadDocument(tempFile);
+    const r = await loadDocumentWithPlugins(tempFile);
     expect(r).toSatisfy(
         (r) => r.success,
         `Failed to load schema: ${(r as any).errors?.map((e: any) => e.toString()).join(', ')}`,
@@ -131,7 +131,7 @@ export async function loadSchemaWithError(schema: string, error: string | RegExp
     // create a temp file
     const tempFile = path.join(os.tmpdir(), `zenstack-schema-${crypto.randomUUID()}.zmodel`);
     fs.writeFileSync(tempFile, schema);
-    const r = await loadDocument(tempFile);
+    const r = await loadDocumentWithPlugins(tempFile);
     expect(r.success).toBe(false);
     invariant(!r.success);
     if (typeof error === 'string') {
diff --git a/packages/testtools/src/utils.ts b/packages/testtools/src/utils.ts
new file mode 100644
index 00000000..75f48ee8
--- /dev/null
+++ b/packages/testtools/src/utils.ts
@@ -0,0 +1,7 @@
+import { loadDocument } from '@zenstackhq/language';
+import path from 'node:path';
+
+export function loadDocumentWithPlugins(filePath: string) {
+    const pluginModelFiles = [path.resolve(__dirname, '../node_modules/@zenstackhq/plugin-policy/plugin.zmodel')];
+    return loadDocument(filePath, pluginModelFiles);
+}
diff --git a/pnpm-lock.yaml b/pnpm-lock.yaml
index eff0e66f..aa32c4a2 100644
--- a/pnpm-lock.yaml
+++ b/pnpm-lock.yaml
@@ -282,9 +282,6 @@ importers:
       '@zenstackhq/runtime':
         specifier: workspace:*
         version: link:../../runtime
-      '@zenstackhq/sdk':
-        specifier: workspace:*
-        version: link:../../sdk
       kysely:
         specifier: 'catalog:'
         version: 0.27.6
@@ -510,6 +507,9 @@ importers:
 
   samples/blog:
     dependencies:
+      '@zenstackhq/plugin-policy':
+        specifier: workspace:*
+        version: link:../../packages/plugins/policy
       '@zenstackhq/runtime':
         specifier: workspace:*
         version: link:../../packages/runtime
diff --git a/samples/blog/main.ts b/samples/blog/main.ts
index 8bbfb5bf..d0c82fc0 100644
--- a/samples/blog/main.ts
+++ b/samples/blog/main.ts
@@ -1,3 +1,4 @@
+import { PolicyPlugin } from '@zenstackhq/plugin-policy';
 import { ZenStackClient } from '@zenstackhq/runtime';
 import SQLite from 'better-sqlite3';
 import { sql, SqliteDialect } from 'kysely';
@@ -89,6 +90,17 @@ async function main() {
         },
     });
     console.log('User found with computed field:', userWithMorePosts);
+
+    // policy-enabled read
+    const authDb = db.$use(new PolicyPlugin());
+    const user1Db = authDb.$setAuth({ id: user1.id });
+    const user2Db = authDb.$setAuth({ id: user2.id });
+
+    console.log('Posts readable to', user1.email);
+    console.table(await user1Db.post.findMany({ select: { title: true, published: true } }));
+
+    console.log('Posts readable to', user2.email);
+    console.table(await user2Db.post.findMany({ select: { title: true, published: true } }));
 }
 
 main();
diff --git a/samples/blog/package.json b/samples/blog/package.json
index 9298036c..8e56eacb 100644
--- a/samples/blog/package.json
+++ b/samples/blog/package.json
@@ -15,6 +15,7 @@
     "license": "MIT",
     "dependencies": {
         "@zenstackhq/runtime": "workspace:*",
+        "@zenstackhq/plugin-policy": "workspace:*",
         "better-sqlite3": "^12.2.0",
         "kysely": "catalog:"
     },
diff --git a/samples/blog/zenstack/models.ts b/samples/blog/zenstack/models.ts
index 86b941a1..608e9397 100644
--- a/samples/blog/zenstack/models.ts
+++ b/samples/blog/zenstack/models.ts
@@ -9,8 +9,6 @@ import { schema as $schema, type SchemaType as $Schema } from "./schema";
 import { type ModelResult as $ModelResult, type TypeDefResult as $TypeDefResult } from "@zenstackhq/runtime";
 /**
  * User model
- *
- * Represents a user of the blog.
  */
 export type User = $ModelResult<$Schema, "User">;
 /**
diff --git a/samples/blog/zenstack/schema.ts b/samples/blog/zenstack/schema.ts
index 4ca14e3e..fa51f40f 100644
--- a/samples/blog/zenstack/schema.ts
+++ b/samples/blog/zenstack/schema.ts
@@ -69,6 +69,10 @@ export const schema = {
                     relation: { opposite: "user" }
                 }
             },
+            attributes: [
+                { name: "@@allow", args: [{ name: "operation", value: ExpressionUtils.literal("read,create") }, { name: "condition", value: ExpressionUtils.literal(true) }] },
+                { name: "@@allow", args: [{ name: "operation", value: ExpressionUtils.literal("all") }, { name: "condition", value: ExpressionUtils.binary(ExpressionUtils._this(), "==", ExpressionUtils.call("auth")) }] }
+            ],
             idFields: ["id"],
             uniqueFields: {
                 id: { type: "String" },
@@ -132,6 +136,9 @@ export const schema = {
                     ]
                 }
             },
+            attributes: [
+                { name: "@@allow", args: [{ name: "operation", value: ExpressionUtils.literal("all") }, { name: "condition", value: ExpressionUtils.call("check", [ExpressionUtils.field("user")]) }] }
+            ],
             idFields: ["id"],
             uniqueFields: {
                 id: { type: "String" },
@@ -188,6 +195,10 @@ export const schema = {
                     ]
                 }
             },
+            attributes: [
+                { name: "@@allow", args: [{ name: "operation", value: ExpressionUtils.literal("read") }, { name: "condition", value: ExpressionUtils.field("published") }] },
+                { name: "@@allow", args: [{ name: "operation", value: ExpressionUtils.literal("all") }, { name: "condition", value: ExpressionUtils.binary(ExpressionUtils.field("author"), "==", ExpressionUtils.call("auth")) }] }
+            ],
             idFields: ["id"],
             uniqueFields: {
                 id: { type: "String" }
diff --git a/samples/blog/zenstack/schema.zmodel b/samples/blog/zenstack/schema.zmodel
index aeccb56f..708afb9e 100644
--- a/samples/blog/zenstack/schema.zmodel
+++ b/samples/blog/zenstack/schema.zmodel
@@ -9,6 +9,10 @@ enum Role {
     USER
 }
 
+plugin policy {
+    provider = '../node_modules/@zenstackhq/plugin-policy/dist/index.js'
+}
+
 type CommonFields {
     id        String   @id @default(cuid())
     createdAt DateTime @default(now())
@@ -16,8 +20,6 @@ type CommonFields {
 }
 
 /// User model
-///
-/// Represents a user of the blog.
 model User with CommonFields {
     email     String   @unique
     name      String?
@@ -25,6 +27,9 @@ model User with CommonFields {
     role      Role     @default(USER)
     posts     Post[]
     profile   Profile?
+
+    @@allow('read,create', true)
+    @@allow('all', this == auth())
 }
 
 /// Profile model
@@ -33,6 +38,7 @@ model Profile with CommonFields {
     age    Int?
     user   User?   @relation(fields: [userId], references: [id])
     userId String? @unique
+    @@allow('all', check(user))
 }
 
 /// Post model
@@ -42,4 +48,7 @@ model Post with CommonFields {
     published Boolean  @default(false)
     author    User     @relation(fields: [authorId], references: [id])
     authorId  String
+
+    @@allow('read', published)
+    @@allow('all', author == auth())
 }
diff --git a/tests/e2e/orm/policy/migrated/current-model.test.ts b/tests/e2e/orm/policy/migrated/current-model.test.ts
index 04c9a30a..0ceb96c3 100644
--- a/tests/e2e/orm/policy/migrated/current-model.test.ts
+++ b/tests/e2e/orm/policy/migrated/current-model.test.ts
@@ -158,7 +158,7 @@ describe('currentModel tests', () => {
             createPolicyTestClient(
                 `
             model User {
-                id String @default(currentModel())
+                id String @id @default(currentModel())
             }
             `,
             ),
diff --git a/tests/e2e/orm/policy/migrated/current-operation.test.ts b/tests/e2e/orm/policy/migrated/current-operation.test.ts
index 2b1610c9..3cbae4ca 100644
--- a/tests/e2e/orm/policy/migrated/current-operation.test.ts
+++ b/tests/e2e/orm/policy/migrated/current-operation.test.ts
@@ -127,7 +127,7 @@ describe('currentOperation tests', () => {
             createPolicyTestClient(
                 `
             model User {
-                id String @default(currentOperation())
+                id String @id @default(currentOperation())
             }
             `,
             ),
diff --git a/tests/e2e/orm/scripts/generate.ts b/tests/e2e/orm/scripts/generate.ts
index b4f78958..9d59db73 100644
--- a/tests/e2e/orm/scripts/generate.ts
+++ b/tests/e2e/orm/scripts/generate.ts
@@ -1,4 +1,5 @@
 import { loadDocument } from '@zenstackhq/language';
+import type { Model } from '@zenstackhq/language/ast';
 import { TsSchemaGenerator } from '@zenstackhq/sdk';
 import { glob } from 'glob';
 import path from 'node:path';
@@ -17,11 +18,18 @@ async function main() {
 async function generate(schemaPath: string) {
     const generator = new TsSchemaGenerator();
     const outputDir = path.dirname(schemaPath);
-    const result = await loadDocument(schemaPath);
+
+    // isomorphic __dirname
+    const _dirname = typeof __dirname !== 'undefined' ? __dirname : path.dirname(fileURLToPath(import.meta.url));
+
+    // plugin models
+    const pluginDocs = [path.resolve(_dirname, '../../node_modules/@zenstackhq/plugin-policy/plugin.zmodel')];
+
+    const result = await loadDocument(schemaPath, pluginDocs);
     if (!result.success) {
         throw new Error(`Failed to load schema from ${schemaPath}: ${result.errors}`);
     }
-    await generator.generate(result.model, outputDir);
+    await generator.generate(result.model as Model, outputDir);
 }
 
 main();